JPS62120957A - Universal head in machine tool - Google Patents

Abstract

PURPOSE:To make a curve and a linear groove machinable only setting a work at one time, by connecting one of a first arm to the side of a spindle head and making it rotatable at the specified angle to a spindle of the spindle head, while connecting a second arm to the other end of the first arm, and making it rotatable at the specified angle. CONSTITUTION:When a servomotor 92 of a first driving device is operated, a first arm 25 is rotatable as far as the specified angle to a spindle head 11. And, when a servomotor 63 of a second driving device is operated, a second arm 28 is rotatable as far as the specified angle to the first arm 25. Therefore, when a tool 61 of the second arm 28 is directed to horizontal, vertical directions, etc., whereby a spindle is rotated, curved and linear grooves, etc., are machined on a work W.

Description

[Detailed description of the invention] Industry-F 1! I! The present invention relates to a universal head for machine tools.

Go ahead LL Machine tools are CN C (Computer N um
The erical control device allows complex control [1-] to be performed.

For example, a workpiece such as a vertical machining tip is
It has a table that moves in the X%Y direction and a spindle head that moves in the Z direction (vertical direction) so that workpieces can be processed easily.

These are controlled by CNC equipment.

1. With this type of machine tool, for example, a linear groove is machined on the first surface of a rectangular parallelepiped workpiece, and a circular groove is machined on the second surface adjacent to the first surface. Consider the case.

First, the workpiece is fixed on a table with the first side facing the tool above. Lower the spindle head, move the table horizontally, and cut a straight groove on the first surface with a tool. Then, raise the spindle head once.

Next, the workpiece is removed from the table and fixed again so that the second surface faces the tool. Then, lower the spindle head, move the X1Y table, and cut a circular groove on the second surface with a tool.

In order to perform various types of machining, the workpiece must be set on the table twice (at least twice), which hinders the improvement of machining efficiency and prevents automation of the work.

The purpose of this invention is to solve the above-mentioned problems and provide a universal head for machine tools that can process curved or straight grooves on a workpiece by setting the workpiece once. do.

Go to 11 LL In this invention, one end of the first arm is connected to the spindle head side, the first arm is rotatable by a predetermined angle with respect to the spindle head by a first drive means, and the center axis of the other end of the first arm is intersects the central axis of the main shaft at a predetermined angle, one end of the second arm is connected to the other end of the first arm, and the second arm is rotated by a predetermined angle with respect to the first arm by a second drive means. It is possible and
The central axis of the other end of the second arm intersects the central axis of the other end of the first arm at a predetermined angle, and a transmission means is supported along each central axis from inside the first arm to inside the second arm. ,
One end of the transmission means is connected to the main shaft and of the second arm (l!
! A tool is set at the other end of the transmission means on the end side, and the universal head for a machine tool is configured such that the tool can be rotated via the transmission means by rotation of the main shaft.

I'm going to say LL; See Figure 3.

On the spindle head 11 side? One end 26 of the R1 arm 25 is connected. The first arm 25 is rotatable relative to the spindle head 11 by a first drive means 91 by a predetermined angle about the central axis 1.1 of the main shaft 18 of the spindle head 11. The other end 27 of the first arm 25
The central axis L2 passing through is at a predetermined angle θ with the central axis L1 of the main shaft 18.
They intersect at 1.

The other end 27 of the first arm 25 has one end 2 of the second arm 28.
Connect 9. The second arm 28 is rotatable by a predetermined angle relative to the first arm 25 about the central axis L2 of the other end 27 of the first arm 25 by a second driving means 62.

The center axis L3 of the other end 30 of the second arm 28 is the first arm 2
The transmission means 31 intersects with the central axis L2 of the other end 27 of 5 at a predetermined angle θ2, and is supported along each central axis from the inside of the first arm 25 to the inside of the 27th-1128th arm.

One end of the transmission means 31 is connected to the main shaft 18, and the other end of the transmission means 31 located on the other end 30 side of the second arm 28 has a
Set the tool 61.

The tool 61 can be rotated by the rotation of the main shaft 18 via the transmission means 31.

By operating the servo motor 92 of the first drive means 91, the first arm 25 can rotate by a predetermined angle with respect to the spindle head 11. By operating the servo motor 63 of the second drive means 62, the second arm 28 can rotate by a predetermined angle with respect to the first arm 25.

Therefore, by rotating the main shaft 18 with the tool 61 of the second arm 28 in the horizontal or vertical direction, it is possible to process a curved or straight groove on the workpiece.

1 and 2 show a machine tool 2 equipped with a universal head 1 according to an embodiment of the invention.

This machine tool 2 has a main body 3 of the machine tool, CNCVt'a
4 and an operation panel 5.

The main body 3 is a vertical machining center.

A first table 7 and a second table 8 are provided on the base 6 of the main body 3. The first table 7 can be moved on the second table 8 in the direction of arrow X in FIG. 1 by a servo motor 9. The second table 8 can be moved on the base 6 in the direction of arrow Y in FIG. 2 by a servo motor 1o. Spindle head 11 of main body 3
can be moved up and down along the rails 13 of the column 12 in the two directions of arrows in FIG. 2 by a servo motor 14.

The main body 3 also includes an automatic tool changer 15 and a tool magazine 16.

The universal head 1 is shown in FIG. The universal head 1 is set at the lower end of the spindle head 11.

The main shaft 18 is rotatably supported within the main shaft head 11 via bearings 19 to 21. Inside this main shaft 18 is a sleeve 2.
2' and the tapered support part 23 are attached. A collet 24 is inserted into this sleeve 22.

One end of the base portion 90 of the universal head 1 is attached to the attachment portion 11a of the spindle head 11 via a screw 11b.

One end 26 of the first arm 25 is connected to the other end of the base 90. One end 26 of the first arm 25 is engaged with a mounting portion 90a of the base portion 90. This first arm 25 is rotatable relative to the base 90.

The first arm 25 is bent at an intermediate position, and is aligned with the central axis 1.1 of the main shaft. Central axis L of the other end 27 of the A1 arm 25
2 intersect at an angle θ1, preferably 45″′.

A second arm 28 is connected to the other end 27 of the first arm 25 . That is, the other end 27 of the first arm 25 is inserted into the space 28a of the second arm 28, and one end 29 of the second arm 28 is engaged with the attachment portion 27a of the other end 27. This second arm 28 is rotatable relative to the first arm 25. This second arm 28 is bent at its middle part, and the center axis L2 of the two ends of the second arm 28 and the center axis L3 of the other end 30 of the second arm 28 intersect at an angle θ2, preferably 45''.

Next, the transmission means 31 supported along the central axes 1 to L3 of the first arm 25 and the second arm 28 will be explained.

The tapered portion 32 a of the holder 32 is fitted into the tapered support portion 23 of the main shaft 18 . The pull stud 33 of the holder 32 is fitted into the collet 24 and pulled upward.

The holder 32 is prevented from rotating about the main axis 18 via a stopper 11c and a screw 11d. Each central axis of the holder 32 and its shaft 34 coincides with the central axis L'1 of the main shaft 18. The shaft 34 is rotatably mounted within one end 26 of the first arm 25 via bearings 35a, 36a, 35, 36. On the other hand, a shaft 43 is rotatably supported at the other end 27 of the first arm 25 via bearings 38-42. The central axis of this shaft 43 coincides with the central axis L2. A bevel gear 44- is provided at the upper and lower ends of the shaft 43.
and 45 are set respectively. The bevel gear 44 and the bevel gear 37 attached to the shaft 34 are located in the space 25a of the first arm 25 and mesh with each other.

A shaft 46 is rotatably supported at the other end of the second arm 28 via bearings 47 to 50.

The central axis of this shaft 46 coincides with the central axis L3. A bevel gear 51 is attached to one end of the shaft 46. The bevel width 51 and the bevel width 45 are located within the space 28a of the second arm 28 and mesh with each other. axis 46
The taper portion 54 of the tool holder 53 is inserted into the taper support portion 52 by one inch. The pull stud 55 of the tool holder 53 is fixed by a biasing means 56 provided within the shaft 46. This biasing means 56 consists of a spring 57 and a ball 58. The tool holder 53 is prevented from rotating with respect to the shaft 46 by a screw 59 and a stopper 60. Further, a tool 61 is attached to the tool holder 53.

This tool is, for example, an end mill.

Next, the first driving means 91 will be explained. The servo motor 92 is attached to the other end of the base 90. Servo motor 92
A worm 93 is attached to the output shaft 95 of the motor. A worm wheel 94 is attached to one end 26 of the first arm 25 . This worm wheel 94 and worm 9
3 is meshing. By rotating the servo motor 92, the first arm 25 is rotated about the central axis L1 in the direction of arrow P'.

Next, the second driving means 62 will be explained. The servo motor 63 is attached to the other end 27 of the first arm 25. A worm 65 is attached to the output shaft 64 of the servo motor 63. On the other hand, a worm wheel 66 is attached to one end 29 of the second arm 28. The worm wheel 66 and the worm 65 mesh with each other.

By rotating the servo motor 63, the second arm 28 can be rotated in the direction of arrow R about the central axis L2.

Servo motor 63.92 and the already mentioned servo motor 9
．． For example, a DC servo motor can be used as the motor 10114. Further, the main shaft 18 can be rotated by a motor 18a shown in FIG.

Next, the control system of the servo motors 63.92, 9.10.14 will be explained with reference to FIG. .

It incorporates four CNCR devices and a central processing unit (hereinafter referred to as CPU) 67 as shown in FIG.

The NO program of the NO chip 776 is read by the tape reader 77 and temporarily stored on, for example, seven floppy disks via the address/data bus AD.

The servo system 68 that controls the servo motor 63 is operated by the CPU 6
7 via address/data bus AD.

Further, each servo system 69 to 71.96 that controls the servo motors 9, 10, 14, and 92 is similarly connected to the CPU.

The servo systems 68 to 71.96 are well-known and have similar configurations, and the servo system 68 will be explained as a representative. Note that the servo system 96 includes symbols 72 to 75 and 80 of the servo system 68.
〜'82 has the same '?' , J No. 172・
~175.180~182 is written, servo system 69.70
71 is omitted from illustration to simplify the drawing.

The position control section 72 includes a pulse shaping/direction determining circuit 73, a deviation counter 74, and a D/A converter 75.

The NO program is input from the floppy disk 79 to the CPU 67. The CPU 67 sends a movement command pulse 72a and a command code 72b for determining the rotational direction of the servo motor 63 to the pulse shaping/direction determining circuit 73 based on this NO program.

A speed control section 80 is connected to a subsequent stage of the position control section 72. Speed control section 801. , is connected to the servo motor 63. A tacho generator 81 and a pulse generator 82 are connected to the output shaft of the servo motor 63.

The tacho generator 81 is used to detect the rotational speed of the servo motor 63. The output voltage of the tacho generator 81 is proportional to the rotation speed, and the (^ character) of the output voltage is determined by the rotation direction of the servo motor 63.

The pulse generator 82 detects the rotation angle of the servo motor 63. The number of pulse outputs of the pulse generator 82 is proportional to the rotational movement, and the polarity of the pulse output is determined by the rotational movement direction of the servo motor 63.

The tacho generator 81 is connected to the speed control section 80. The pulse generator 82 is connected to a pulse shaping/direction determining circuit 73.

The deviation counter 74 outputs the difference (sludge pulse) between the number of movement command pulses 72 and the number of movement feedback pulses fed back from the pulse generator 82 as an error output voltage. The magnitude of this output voltage is proportional to the magnitude of the difference, and the polarity of the output is determined by the polarity of the difference.

This error output voltage, which is a digital value, is converted into an analog value using a D/A converter and is applied to the speed control section 80 as a speed command voltage.

The speed control unit 8o compares the speed feedback voltage from the tacho generator 81 and the speed command voltage. The voltage difference between the two is amplified. The speed of the servo motor 63 is controlled so that the voltage difference between the two approaches zero.

At the beginning of the rotation amount of the servo motor 63, the movement command pulse 7
2a is input to the deviation counter 74 via the pulse shaping/direction determining circuit 73, the counter 74 integrates the pulses. This droop pulse is converted into a speed command voltage by the D/A converter 75 and inputted to the speed control section 80.

Therefore, the servo motor 63 starts rotating. When the servo motor 63 starts rotating, a pulse proportional to the rotation angle is generated from the pulse generator 82 and the deviation counter 74 generates a pulse proportional to the rotation angle.
is input. As a result, the accumulated pulses in the 11-digit difference counter 74 are subtracted.

If the movement command pulse 72a is continuously input, the servo motor 63 rotates continuously and the deviation counter 74 maintains a constant number of droop pulses.

The rotation speed of the servo motor 63 is proportional to the frequency of the movement command pulse 72a.

When the input of the movement command pulse 72a stops, the servo motor 63 rotates until the accumulated pulse of the FA difference counter 74 becomes zero, and then stops.

For example, based on the number of movement command pulses 72a, the second arm 28 is placed in the state shown in FIG. 7 relative to the first arm 25 with reference to FIGS. 4, 8 and 9. The state shown in FIG. 8 can be changed by rotating 180° from the state shown in FIG.

Similarly to the servo motor 63, the servo motor 92 also controls the base 9 based on the number of movement command pulses 172a, for example.
It is possible to rotate 360° with respect to o.

The servo motors 9.10.14 of the servo systems 69-71 are similarly controlled. That is, the spindle head 11 and the table 7.8 can each be moved to a predetermined position based on the movement command pulse and the command code.

By the way, the main shaft motor 18a is rotated at a predetermined rotation speed according to a command from the sequence control section 83. This sequence control section 83 is connected to the address /7'-TABUS AD of the CPU 67 via an interface 84. Each of the servo motors 9, 10, 14, 63, 92 and the main shaft motor 18a are individually activated by a command from the CPU 67. In addition, the operation panel 5 is connected to the C
The PU 67 is connected to the sequence control section 83 and to, for example, a limit switch (not shown) of the main body 3.

Next, based on the NC program, for example, a circular groove 97 and a straight groove 87 are machined on the upper surface W2 of the workpiece W.
A case will be described in which a linear groove 86 is formed on the side surface W1.

(See FIGS. 5 to 8) First, as shown in FIG. 5, the workpiece W is set on the first table 7 via the stopper 85. Press the automatic operation button of operation W145 to move the first table 7 to the servo motor 9.
Move it in the direction of arrow X by (see Figure 1), and
The work W is positioned at a predetermined position by moving the second table 8 in the direction of arrow Y by the servo motor 10. On the other hand, the second arm 28 of the universal head 1 is
It has already been rotated 180 degrees from the state shown in FIG. 3 to the state shown in FIG.

That is, the tool 61 is directed vertically downward and the workpiece W
It faces the upper surface W2 of.

Next, the spindle head 11 is lowered in the direction of arrow Z by the servo motor 14, and the spindle motor 18a (see FIG. 1) is rotated to turn the tool 61.

Cut R61 into the upper surface W2 to a predetermined depth. Then, by operating the servo motor 92, the first arm 25 and the second arm 28
is rotated 360° about the spindle head 11.

By doing so, a circular groove 97 as shown in FIG. 6 can be formed. After machining, the spindle head 11 is raised.

Move the first table 7 and the second table 8 (see Figs. 1 and 2), position the work W to a new predetermined position as shown in Fig. 7, and lower the spindle head 11 to move the work W. The tool 61 is cut into the upper surface W2. Then, move the second table 8 in the direction of the arrow in FIG. 2 (to the right).

A groove 87 is formed in the upper surface W2. Then, the spindle head 11 is upper bounded.

Subsequently, the first table 7 and the second table 8 are moved again. In this way, the workpiece W is further positioned at a new predetermined position as shown in FIG. The second arm 28 of the universal head 1 is rotated 180° from the state shown in FIG.
Rotate and direct the tool 61 horizontally to the left in the drawing, as shown in FIGS. 3 and 8. Then, the spindle head 11 is lowered by the servo motor 14 so that the tool 61 and the side surface W1 face each other.

The main shaft motor 18a is rotated to turn the tool 61, and the first table 7 is moved rightward in FIG. 5, so that the tool 61 cuts into the side surface W1 of the workpiece W. Then, the second table 8 is
Move in the direction of arrow Y (rightward) in the figure and fill the side surface W1 with 86
form.

In this way, by simply setting the workpiece W on the first table 7 once and rotating the arm 28 of the universal head 1 by a predetermined angle, the workpiece can be machined on multiple sides.

The above is just one processing example. Servo motor 9
2.63 can be operated at the same time to process complex three-dimensional curves.

By the way, the servo motor is not limited to a DC servo type, but may be an AC servo type.

Further, a stepping motor may be used instead of the servo motor.

Also, the angle θ1.0 at which the central axes L1, L2, and L3 intersect
If angle 2 is set at 45 degrees, the tool 61 can be applied perpendicularly to the top and side surfaces of the rectangular parallelepiped workpiece W. but,
If a universal head with angles θ1 and θ2 set to other than 45″ is prepared, the desired angle C tool 61 can be applied to the upper surface of the workpiece.

dan)] (7) 9)> Comb As explained above, according to the present invention, curved or straight grooves can be formed on the workpiece by simply setting the workpiece once on the table.

[Brief explanation of drawings]

Fig. 1 is a front view showing a machine tool equipped with the universal head of this invention, Fig. 2 is a side view of the same machine tool, Fig. 3 is a sectional view of the universal head, and Fig. 4 is a servo system and CNC equipment. δ, etc., Figure 5 is a diagram showing an example of machining by a universal head, Figure 6 is a perspective view of a machined workpiece, and Figures 7 and 8 are examples of machining a workpiece by a universal head. FIG. 1. Universal head 2. Machine tool 4. CNCM! 9.10,14. 63.92. , Servo motor 18 , Main shaft 25 , First arm 28 , Second arm 31 , Transmission means 61 , Tool 62 , , Second driving means 90 , Base 91 , First driving means

Claims (2)

[Claims] (1) One end of the first arm is connected to the spindle head side, the first arm is rotatable by a predetermined angle with respect to the spindle head by a first drive means, and the center axis of the other end of the first arm is connected to the spindle head side. It intersects the central axis at a predetermined angle, and the other end of the first arm has a second
One end of the arm is connected, and the second arm is rotatable by a predetermined angle with respect to the first arm by a second driving means.
The central axis of the other end of the arm intersects the central axis of the other end of the first arm at a predetermined angle, and transmission means is supported along each central axis from the inside of the first arm to the inside of the second arm. In a machine tool, one end of the means is connected to the main shaft, and a tool is set at the other end of the transmission means on the other end side of the second arm, and the tool can be rotated via the transmission means by rotation of the main shaft. universal head. (2) The central axis of the other end of the first arm intersects the central axis of the main shaft at an angle of 45°, and the central axis of the other end of the second arm intersects the central axis of the other end of the first arm at an angle of 45°. Universal heads in a machine tool according to claim 1, which intersect at an angle of .degree.